/Engine/Source/Runtime/Core/Public/GenericPlatform/GenericPlatformMemory.h
This function sets AllocFunction and FreeFunction and returns true, or just returns false. These functions are the platform dependant low low low level functions that LLM uses to allocate memory.
static bool GetLLMAllocFunctions ( void *(*&)(size_t) OutAllocFunction, void(*&)(void *, size_t) OutFreeFunction, int32 & OutAlignment )